Buyer BEWARE!

BEWARE EVERYONE!!
I booked economy class tickets for my husband & I to travel from Boston to Munich, through Dublin. Before departing I received an email asking if I'd like to "bid" on first class. I thought, oh, it's worth a bid. I bid very low, but then received a response telling me that my $650 per seat bid was accepted. I almost had a heart attack! But, then I noticed it told me I could cancel the "bid", & I cancelled it. I was only bidding on part of our journey. From Dublin to Munich was not included. I received an email immediately telling me it was cancelled. I saved that email, & forgot about it. While in Europe, my cell phone was stolen. I no longer had access to my email except if in my hotel. We were exhausted each night so I rarely checked it.
We went to check in at the airport & ran into a problem there, as the computer terminal was not working properly. The woman trying to check us in, was very apologetic & frustrated & eventually had to move us to another line. We didn't complain, and we were very pleasant. When we boarded our second part of the journey, from Dublin to Boston, we were escorted to first class. We were shocked! We thought that we were upgraded, possibly because of the problem with the check in. We were completely happy with the airline up to this point & now we were over the top thrilled! We enjoyed it very much, & told everyone of our great luck.
HOWEVER, once home, used my computer to check my email, and I found another email, sent near the end of our trip telling me "Congratulations! Your bid for $650 per seat was accepted for the return flight!!! I never made a bid for that. It seems, when you place the first bid, it automatically bids on the return as well.
I complained to the air line, & they said since I let them seat us in first class & didn't object, they wouldn't refund me (they had charged my credit card for an additional &1,300.00 for the flight!).
This is a complete Rip off, & terribly dishonest. I was never so disappointed! I had been so happy with this air line & now I am sick about the treatment I received! It's a horrible way to treat a customer, & should be illegal. We are retired & had saved for this trip for a long time. If we could afford first class I wouldn't have booked economy! I hope word spreads about this policy, because it is very deceptive & I don't want anybody else to be taken in by it!